1. Field of the Invention
The present invention relates to a connector board for connecting an electronic component to a printed circuit board. More particularly, it relates to a connector board (or “socket”) which is so designed that, when the electronic component of a CPO, an MPU or the like is pushed against it, the electrode terminals of the electronic component and those of a printed circuit board can be electrically connected through electrode portions disposed in the connector board.
2. Description of the Related Art
One known type of connector board for an electronic component is so constructed that, when the electronic component is pushed against the connector board, the electrical contact between the electrode terminals of the electronic component and the electrode portions of the connector board is maintained, while the electrode portions of the connector board are connected to the electrode terminals of a printed circuit board (refer to, for example, U.S. Pat. No. 6,004,141).
With the connector board for the electronic component, a clamping member is coupled to one end edge portion of the socket body, and it is swung about in the coupled state, to thereby urge the electronic component onto the connector board. A hook which is mounted to the other end of the clamping member is engaged with an engaging portion of the connector board. Thus, the electronic component is fixed (mounted) on the connector board, and the electrical contact between the electrode terminals of the electronic component and the electrode portions of the connector board is maintained.
As shown in FIG. 15, each of the electrode portions of the connector board includes a sliding contact 10 which comes into contact with the corresponding electrode terminal of the electronic component, and a spring contact 20, which is the form of a leaf spring, lies in contact with the sliding contact 10. The sliding contact 10 and the spring contact 20 are arranged in opposition within the recess 40 of the connector board 30.
When the electronic component is pushed against the connector board 30, the contact point 50 between the sliding contact 10 and the spring contact 20 is slidably moved in a direction b, perpendicular to a pushing direction a. In turn, the degree of pressure of the contact between the sliding contact 10 and the spring contact 20 increases in proportion to the amount of movement of the sliding contact 10 owing to the resilience of the spring contact 20.
In a connector board thus constructed, electrical contact between the electrode terminals of the electronic component and the electrode portions of the connector board is not harmed by the attachment or detachment of the electronic component. Moreover, the electrode portions are comparatively simple in structure and are easy to fabricate.
However, such a connector board remains unsatisfactory for the reasons stated below. Since each electrode portion of the connector board has a so-called “two-piece contact structure”, consisting of the sliding contact 10 and the spring contact 20, the contact point 50 between the sliding contact 10 and the spring contact 20 may unintentionally slide to make the contact pressure unstable, depending upon the state of the contact position between the two. Moreover, the contacts have complicated shapes and are in two parts, so that the workability and assembly of the contacts are difficult, and the cost thereof is comparatively high. Further, since the displacement of the spring contact 20 is within the connector board 30, the connector board 30 itself must be sufficiently thick to allow for the displacement of the spring contact 20.